Business Segment Information - Customers Percentage of Sales (Details) - USD ($) $ in Millions	12 Months Ended
	May 31, 2024	May 31, 2023	May 31, 2022
Business Segment Information
Net sales	$ 2,318.9	$ 1,990.5	$ 1,820.0
U.S. Department of Defense, other U.S. government agencies and their contractors
Business Segment Information
Net sales	576.1	577.0	620.0
Parts Supply
Business Segment Information
Net sales	967.0	818.4	678.3
Parts Supply | U.S. Department of Defense, other U.S. government agencies and their contractors
Business Segment Information
Net sales	99.3	111.0	106.7
Parts Supply | Commercial
Business Segment Information
Net sales	800.6	645.0	510.7
Parts Supply | Government and defense
Business Segment Information
Net sales	166.4	173.4	167.6
Repair & Engineering
Business Segment Information
Net sales	640.1	533.4	470.7
Repair & Engineering | U.S. Department of Defense, other U.S. government agencies and their contractors
Business Segment Information
Net sales	61.0	48.5	56.2
Repair & Engineering | Commercial
Business Segment Information
Net sales	574.1	478.5	407.0
Repair & Engineering | Government and defense
Business Segment Information
Net sales	66.0	54.9	63.7
Integrated Solutions
Business Segment Information
Net sales	641.9	546.9	596.8
Integrated Solutions | U.S. Department of Defense, other U.S. government agencies and their contractors
Business Segment Information
Net sales	356.6	340.2	394.5
Integrated Solutions | Commercial
Business Segment Information
Net sales	257.1	197.0	163.9
Integrated Solutions | Government and defense
Business Segment Information
Net sales	384.8	349.9	432.9
Expeditionary Services
Business Segment Information
Net sales	69.9	91.8	74.2
Expeditionary Services | U.S. Department of Defense, other U.S. government agencies and their contractors
Business Segment Information
Net sales	59.2	77.3	62.6
Expeditionary Services | Commercial
Business Segment Information
Net sales	6.1	8.3	2.2
Expeditionary Services | Government and defense
Business Segment Information
Net sales	$ 63.8	$ 83.5	$ 72.0
Customer | Total sales | U.S. Department of Defense, other U.S. government agencies and their contractors
Business Segment Information
Percentage of total sales	24.80%	29.00%	34.10%